title: Forearm training reduces the exercise pressor reflex during ischemic rhythmic handgrip.
abstract: We examined the effects of unilateral, nondominant forearm training (4 wk) on blood pressure and forearm metabolites during ischemic and nonischemic rhythmic handgrip (30 1-s contractions/min at 25% maximal voluntary contraction). Contractions were performed by 10 subjects with the forearm enclosed in a pressurized Plexiglas tank to induce ischemic conditions. Training increased the endurance time in the nondominant arm by 102% (protocol 1). In protocol 2, tank pressure was increased in increments of 10 mmHg/min to +50 mmHg. Training raised the positive-pressure threshold necessary to engage the pressor response. In protocol 3, handgrip was performed at +50 mmHg and venous blood samples were analyzed. Training attenuated mean arterial pressure (109 +/- 5 and 98 +/- 4 mmHg pre- and posttraining, respectively, P < 0.01), venous lactate (2.9 +/- 0.4 and 1.8 +/- 0.3 mmol/l pre- and posttraining, respectively, P < 0.01), and the pH response (7.21 +/- 0.02 and 7.25 +/- 0.01, pre- and posttraining, respectively, P < 0.01). However, deep venous O2 saturation was unchanged. Training increased the positive-pressure threshold for metaboreceptor engagement, reduced metabolite concentrations, and reduced mean arterial pressure during ischemic exercise.
authors.affiliation: Milton S. Hershey Medical Center, Pennsylvania State University, Hershey 17033, USA.
authors.forename: S
authors.initials: S
authors.lastname: Mostoufi-Moab
authors.forename: E J
authors.initials: EJ
authors.lastname: Widmaier
authors.forename: J A
authors.initials: JA
authors.lastname: Cornett
authors.forename: K
authors.initials: K
authors.lastname: Gray
authors.forename: L I
authors.initials: LI
authors.lastname: Sinoway
mesh_terms: D000328:Adult; D002245:Carbon Dioxide / Q000097:blood; D015444:Exercise / Q000502:physiology*; D005542:Forearm / Q000098:blood supply / Q000502:physiology*; D006225:Hand / Q000098:blood supply / Q000502:physiology; D018737:Hand Strength / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007511:Ischemia; D008297:Male; D018482:Muscle, Skeletal / Q000098:blood supply / Q000502:physiology; D010101:Oxygen Consumption / Q000502:physiology; D010809:Physical Fitness / Q000502:physiology*; D012039:Regional Blood Flow / Q000502:physiology; D015656:Respiratory Mechanics / Q000502:physiology
chemical_list: D002245:Carbon Dioxide